Functional safety represents a clear differentiator for current and future products in various industries, such as in automotive productions, for example. To achieve corresponding targets in terms of automotive safety integrity level (ASIL), new and enhanced concepts have to be established. To achieve a dedicated ASIL level, different target parameters as failures in time (FIT) rate, diagnostic coverage, SPFM, LPFM, etc., have to achieve a dedicated value.
Modern vehicles include a vast array of sensors, such as air bag sensors, tire pressure sensors, engine sensors, seat belt sensors, and many others. The air bag sensors, for example, provide data about the vehicle's operation (e.g., wheel speed, deceleration, etc.) to an engine control unit (ECU), an airbag control unit (ACU) or other vehicle controller. Based on the data received from the sensors, the control unit can determine when air bags or other sub-system within a vehicle should be operational.
As the number of vehicular sensors increases, integration becomes a serious challenge for automakers. For example, wires connecting an ACU to its corresponding air bag sensors can be several meters long. These wires are a significant cost factor in automotive systems and contribute to the overall weight of the vehicle, but can be reduced by the communication interface. High current can also be consumed by the sensors using current modulation to transmit data to the ECU or other control unit. The high average current consumption can call for heat dissipation mechanisms, which can increase area and reduce reliability. Additionally, high current transmitted along long cables or pathways can generate strong emissions. Thus, reducing the current can reduce operating temperatures and emissions, and thereby increase the device reliability.